Input-output typewriter apparatus

ABSTRACT

A typewriter which is remotely operable or capable of providing signals for remotely operating another typewriter. The typewriter has movable mechanical mechanisms, such as interposers, for operating the character printing and carriage function mechanisms of the typewriter. A mounting board is horizontally mounted to the typewriter frame beneath the typewriter mechanism and a plurality of horizontally operable solenoids are mounted to the underside of the mounting board. The solenoids are connected to the interposers and other mechanical mechanisms by a plurality of connecting rods which extend downwardly from the typewriter mechanisms and then horizontally beneath the mounting board to the plungers of the solenoids. Blade switches are provided which seat in cam follower relationship against a cam lobe portion of the interposers and other typewriter mechanisms for providing output data. Selected ones of the connecting rods are provided with clevises which may be snapped on the standard clevis pins of the interposers.

United States Patent [191 Manson [54] INPUT-OUTPUT TYPEWRITER APPARATUS [75] Inventor: Edwin E. Manson, Harrisburg, Ohio [73] Assignee: MI Inc., Columbus, Ohio [22] Filed: Oct. 8, 1970 [21] Appl. No.: 79,202

[52] US. Cl ..197/19, 197/16 [51] Int. Cl. ..B4lj 5/30 [58] Field of Search ..197/16, 19

[56] References Cited UNITED STATES PATENTS 3,165,190 1/1965 Wenczel ..197/19 3,197,618 7/1965 Stanley et a1. ..197/20 X 3,233,715 2/1966 Flieg ..197/19 3,380,569 4/ 1968 Becking et a1 ..197/20 3,391,774 7/1968 Greer ..197/16 3,414,103 12/1968 Knudson et al 197/20 3,452,851 7/1969 Holmes ..197/19 3,453,379 7/1969 Holmes; ..197/19 X Primary Examirier--Edgar S. Burr Atmrney-Anthony D. Cennamo [111 3,724,630 [451 Apr. 3, 1973 [57] ABSTRACT A typewriter which is remotely operable or capable of providing signals for remotely operatinganother cam follower relationship against a cam lobe portion of the interposers and other typewriter mechanisms for providing output data. Selected ones of the connecting rods are provided with clevises which may be snapped on the standard clevis pins of the interposers.

1 Claim, 26 Drawing; Figures PATENTEDAPR 3 I975 SHEET DlUF 14 TOR SON INVEN EDWIN E. MA

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INVENTOR EDWIN E. MASON W MW ATTORNEYS PATENTEDAPRB 15175 3.724.630

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INVENTOR EDWIN E. MASON www ATTORNEYS 1 INPUT-OUTPUT TYPEWRITER APPARATUS BACKGROUND OF THE INVENTION The invention relates to a typewriter which may be operated from remote equipment by incoming data or which alternatively may be used to provide such data for remote operations.

In recent years, the electric typewriter has become not only a means for communications from one location to another, but also has become a means for communicating with an electronic computer. Many attempts have been made to modify typewriters so that they may be used in any of three alternative functions. The first desired characteristic of a typewriter is that it may be used for its most common purpose of direct manual typing. The second desired function is the generation of data for transmission to a remote location. The third function which is desired is the receipt of data and the transforming of the data into a typewritten message.

Many types of mechanisms have been suggested for converting the standard IBM electric typewritten to add the additional input and output functions. For example, Holmes, in U.S. Pat. No. 3,453,379, has suggested a system which is typical and calls for the positioning of solenoids and micro switches in "many diversed and widely scattered locations throughout the conventional typewriter mechanism. Attaching these types of converting mechanisms to the typewriter requires either factory installation or a rather complex and complete dismantling of the typewriter in order to install the equipment. In many cases the standard typewriter may not be utilized, but rather the typewriter manufacturer must manufacture unique parts for use on input-output typewriters. The consequent result of the complexity of the necessary prior art modifications is a typewriter which is farmore expensive than the standard electric typewriter.

There is, therefore, a need for an input-output typewriter which is manufactured by installing simple rality of blade switches which are mounted in cam follower relationship against cam lobe portions of the mechanical mechanisms.

OBJECTS OF THE INVENTION It is therefore the object of the invention to provide an improved input-output typewriter.

Another object of the invention is to provide mechanisms which may be very quickly and very inexpensively added to a standard IBMI select ric typewriter.

Another object of I the invention is to provide mechanisms which are easily accessible to service personnel for inspection, cleaning and repair.

Another object of the invention is to provide mechanisms which can be attached to the standard IBM selectric typewriter and yet permit the typewriter cabinet to remain substantially unchanged.

Another object of the invention is to provide such mechanisms which can be added to the IBM selectric typewriter without requiring dismantling of the'standard typewriter mechanisms.

Further objects and features of the invention will be apparent from the following specification and claims and easily installed equipment .on the standard typewriter without thev necessity of dismantling the typewriter. There is similarly a need for apparatus which can be added to the standard typewriter and remain accessible for inspection and servicing. Furthermore, there is a need for such equipment which can be added to the standard electric typewriter without causing a substantial enlargement of the cabinet in which the typewriter mechanisms are housed.

SUMMARY OF THE INVENTION gers of the solenoids.

For operating in its output mode to provide data for a remote operation, the typewriter is provided with a pluwhen considered in connectionwith the accompanying drawings illustrating the preferred embodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view in perspective, illustrating .a typewriter platen in relation to the typewriter drive system;

FIG. 2 is a view in perspective, illustrating portions of the typewriter character selection. mechanism and case shift mechanism;

FIG. 3 is a front view of a portion of -a typewriter character selection mechanism;

FIG. 4 and 5 are side views of portions of a typewriter character selection drive mechanism;

FIG. 6 is a view in perspective showing the character selection and back space selection portion of a typewriter;

FIG. 6a is a view in side elevation of the detail of the cycle clutch switch of the invention;

FIG. 6b is a view in side eleveation of the bell crank mechanism of the invention for actuating the cycle clutch bail;

FIG. 6c is a front view of the mechanism illustrated in FIG. 6b;

FIG. 7 is aview. in side elevation along the lines 7-7 of FIG. 6; A

FIG. 8 is a view in side elevation taken generally along the lines 8-8 ofFIG. 6;

FIG. 9 is a side view illustrating the detail of the keylever switch illustrated in FIG. 7;

FIG 10 is a top view and FIG. 10a is a side view-of the pull rod and clevis attachment to the tabtrip lever;

FIG. 11 is a view in side elevation showingthe detail of the solenoid of the switch mechanisms which are added to the standard IBM selectric typewriteraccording to the invention to cooperate with the latch interposers;

FIG. 12 is a bottom view of the electric typewriter showing the mounting board solenoids and switches mounted in their respective positionson the underside of the typewriter;

FIG. 13 is a view in side elevation illustrating the detail of the solenoid structure utilized to operate the carriage function interposers;

FIG. 14 is a bottom view in detail, illustrating the bell crank mechanisms for operating some of the carriage functions illustrated in FIG. 12;

FIG. 15 is a view in perspective, illustrating a typewriter carrier mechanism;

FIG. 16 is a view in perspective, illustrating a portion of the carrier mechanism shown in FIG. 15 together with control mechanisms therefor;

FIG. 17 is a view in perspective, illustrating a typewriter carrier return and an index control mechanism as modified by the present invention;

FIG. 17a illustrates a portion of the mechanisms set out in FIG. 17;

FIGS. 18 and 19 are side views of the typewriter index mechanism; and

FIGS. 20 and 21 are side views of a typewriter case shift mechanism.

In describing the preferred embodiment of the invention illustrated in the drawings, specific terminology will be resorted to for the sake of clarity, however, it is not intended to be limited to the specific terms so selected and it is to be understood that these specific terms include all terms which operate in a similar manner to accomplish a similar purpose.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Character Selection and Printing Referring now to FIG. 1, an electric typewriter motor 11 operates through a motor clutch l5 and a drive belt 12 to provide the typewriter with the power necessary to carry out a selected print operation or function operation. The drive belt operates over a drive pulley 13 which is connected to a cycle shaft 14 through a cycle clutch 16. When the motor 11 is energized and operating, it continuously drives the pulley 13, but only rotates the shaft 14 when clutch 16 is conditioned to transmit torque. Mounted between the ends of shaft 14 are a plurality of cams such as cams 72 and 91 the operation and function of which will be described below. Secured to the end of shaft 14 is a gear 17 which meshes with a gear 18 that drives a filter shaft 19 through gear 21. The gear 17 also drives a print shaft 22 through an idler gear 23 and print shaft gear 24. Thus, each time a print cycle is initiated by a keybutton being depressed the motor 11 drives the cycle shaft 14 which results in the filter shaft 19 and the print shaft 22 1 being driven for as long as the cycle clutch 16 connects the pulley 13 to the shaft 14. An escapement cam 26 on the filter shaft 19 initiates a function operation (space) to accompany each print operation and provides the only function operation which is initiated through the cycle clutch 16.

An operational cam shaft 27 also communicates with the drive pulley 13 and serves as the connection between the source of power 11 and those mechanisms which perform the various function operations. The

IBM selectric typewriter has a print mechanism the operation of which is basically different than the more commonly known typewriters which employ a large number of individual key bars. In the more conventional typewriter, paper is held to a platen which is secured on a carriage which is movable past a given fixed location at which a selected type barstrikes the paper. The IBM selectric typewriter employs a stationary platen for the paper and has a carrier which supports a type head that moves relative to the paper. The type is all located on the type head and by properly positioning the type head relative to the paper prior to having the type head strike the paper, a selected character or symbol is printed. The type head has four rows of characters with all lower case characters on one hemisphere and all upper case characters on the other hemisphere. In order for a selected character to be printed it may be necessary to both rotate and tilt the type head. The mechanisms which perform these functions are best shown on FIG. 2.

A type head 31 is connected (through mechanismnot shown) to a tilt pulley 32 and a rotate pulley 33. Secured to the tilt pulley 32 is a steel band tilt tape 35. The tape 35 extends around a pulley 34, which is mounted on a movable tilt arm 36, over a second pulley 37 which is mounted on a stationaryarm 38. The end of the tape is anchored to a shaft 39 which is secured to a movable type head carrier 30 (see FIG. 15) on which the head 31 and pulleys 32 and 33 are mounted. Since both ends of tilt tape 35 are secured to the movable type head carrier 30, movement of the carrier does not be itself change the angular'position of the tilt pulley 32. The angular position of the tilt pulley 32 is a function of the position of the tilt arm 36, which inturn is a function of the tilt mechanism 41. When the tilt mechanism 41 operates to change the tilt position of the type head 31 the tilt arm 36 is positioned to change the distance between pulleys 34 and 37. The change in distance between these two pulleys is compensated for by rotation of the tilt pulley 32 which produces a tilt movement of the head 31 Secured to the rotate pulley 33 is a rotate tape 46 which extends over a rotate arm pulley 47 and a shift arm pulley 48 before being secured to the shaft 39. The shift arm pulley 48 is stationary except when a shift operation occurs and thus for the purpose of this discussion can be considered as stationary. The pulley 47 mounted on the rotate arm 49 is movable (along with the rotate arm) and provides the means for rotating the head 31 in much the same manner as movement of arm 36 resulted in tilt rotation of the head 31. Rotate mechanism 51 operates through a rotate 'link 52 to position the rotate arm 49 and thus the rotate arm pulley 47. Moving'the pulley 47 relative to the pulley 48 is compensated for by rotation of the spring-loaded rotate pulley 33.

The pulley 48 is secured to the shift arm'53 which is controlled by the shift mechanism 54 to be in one of two positions. In its normal position the type head 31 is operating on the hemisphere which produces lower case characters and symbols, and in its shifted condition the position of the pulley 48 causes rotation of the type head 31 whereby typing produces upper case characters and symbols.

Each time a character keylever button is depressed both the rotate mechanism 51 and the tilt mechanism 41 operate to position the head 31 to that location which results in the printing of the selected character or symbol. The mechanism which translates the depression of a single keylever button into the exact positioning of the head 31 necessary to produce the desired results will now be described.

Referring now to FIGS. 2-5, the tilt mechanism 41 comprises a pair of selector latches 61 and 62 each rotatably connected to one end of a cross lever 63. A link 64 is rotatably connected at one end to cross lever 63 and at its other end to the tilt bell crank 66. Link 64 is pinned to cross lever 63 at a location which is twice as far from selector latch 62 as from selector latch 61.

Each of the latches 61 and 62 includes a forwardly extending end bottomportion 61a and 62a, respectively, and the latches are spring-loaded to a position which positions portions 61a and 62a below a latch bail plate 67.

The latch bail plate 67 forms a portion of the latch bail 68 which is disposed for rotation about a shaft 69. The latch bail 68 carries a roller 71 which contacts a positive selector cam 72 which is mounted on the cycle shaft 14 (see FIG. 1). The positive selector cam 72 has a generally elliptical shape and thus provides a complete cycle of operation for each 180 of revolution. When the cam rotates 90 from the position shown in FIG. 5, the latch bail 68 is urged downwardly with the latch bail plate 67 urging the selector latches along with it. A further 90 rotation of the cam enables the latch bail to return to its initial position. After the initial 40 of rotation of cam 72, those selector latches not withdrawn are positively engaged and those selector latches withdrawn are cleared. At this time the selector latches can be released without disrupting the desired operation. This feature will be shown to be of considerable importance further in the description of the invention.

' The type head 31 (FIG. 2) carries four circular rows of characters 31a, 31b, 31c and 31d. The head has a normal tilt position in which the characters of row 31a are in the print location. The operation of tilt mechanism 41 results in the characters of one of the other rows being moved to the print location. When both of the selector latches 61 and 62 are. pulled downward by the latch bail plate 67, thelink 64 moves down a distance equal to the distance moved by the latch bail plate and produces the maximum movement of tilt link 36 through the ,tilt bell crank 66 This produces a charge of three rows on the type head such that the characters in row 31d are located for printing.

If prior to the latch bail plate 67 moving downwardly the selector latch 61 is urged in a direction which withdraws the lower extending portion 61a from below the latchbail 67, then only the selector latch 62 will move downwardly with the latch bail plate. When only the selector latch 62 moved downwardly, the cross link 63'rotates about the upper portion of selector latch 61 (the upward movement of selector latch 61 being halted by a stop 73) and the downward movement of link 64 is only one-third as great as when both selector latches were pulled down. This one-third greater movement of link 64 produces only a third as much movement in bell crank 66 and consequently only a third as much movement in tilt link 36. Under these conditions the head tilts one row of characters to row 31b. If the selector latch 62 is withdrawn from below the latch bail plate 67 and selector latch 61 is the only latch urged downwardly, then rotation of cross link 63 takes place about the top of latch 62 (stop 74 preventing upwardmovement of latch 62) and the movement of link 64is twice as great as when latch 62 is urged downwardly, and two-thirds as great as when both latches are urged downwardly. This gives rise to a two-row tilt of the type head whereby the characters of row 310 are located for printing.

To summarize, when both latches 61 and 62 are withdrawn from below latch bail plate 67 prior to the latch bail being cammed'downwardly no tilting occurs in the type head and the characters of row 31aare located for printing. When latch 62 iswithdrawn from under the bail plate the head tilts to locate row 31b for printing; when ,latch 61 is withdrawn from below the bail plate the head tilts two rows to row 31c; and when neither of the latches is withdrawn from below the bail plate (thus both latches being urged downwardly with the latching bail) the head tilts to locate the characters of row 31d for printing.

The rotate mechanism 51 is somewhat more complex than the tilt mechanism due to the need to move to more than four different locations. The principle of operation however is basically the same; The rotate mechanism includes three selector latches 76, 77 and 78 plus a five-unit latch 79 which works through fiveunit latch link 81. Each of the selector latches 76, 77 and 78 includes a forwardly extending bottom portion which is disposed below the latch bail 67 unless urged ina direction which withdraws it. The-selector latches 77 and 78 are connected by a cross link 82 which in turn is secured by a first lever 83 to a second cross link 84. Also connected to the cross link 84 is the selector latch 76. The second cross link 84 is connected by a second lever 86 to a balance lever 87. The balance lever 87 is connected tothe rotate bell crank 88 which is connected through rotate link .52 to the rotate arm 49. It is the position of the rotate arm which determines the position of pulley 47 which in turn acts through tape to angularly position the rotate pulley 33. And angular position of pulley 33 determines the -rotate position of head 31. a

When both latches 76 and78 are withdrawn from below the bail plate 67, such that latch 77 is the only latch urged downwardly, there results a rotation of hell crank 88 which is one fifth as great as the maximum rotation possible through the rotate mechanism 51. When latch 78 is the only latch urged downwardly the resulting rotation of bell crank88 is twice that achieved through latch 77 and thus two-fifths the maximum possible rotation. The same rotation of bell crank 88 which is achieved when only latch 78. is' urged downwardly is achieved when latch 76 is the only latch engaging the bail plate during its downward movement. Latch 76, however, is not used for the purpose of achieving a two-unit rotation. To achieve a three-unit rotation, latches 77 and 78 are both allowed to engage the bail plate on its downward movement and latch 76 alone is withdrawn. A four-unit rotation is accomplished by urging latches 76 and 78 down while withdrawing latch 77, and a five unit, or maximum mechanism to produce rotation in both directions. The I mechanism as described so far has only produced rotation of the bell crank 88 in a single direction. For rotation in the opposite direction it is necessary to employ a five-unit latch system which will now be described with reference to FIG. 4.

The five-unit latch system has its own cam 91 which engages a roller 92 carried by a bail 93 which is mounted on a shaft 94 for rotation. The latch 79 is spring urged to a position which normally prevents the bail 93 from rising A lug 96 is secured to the bail 93 and engages the bottom of the latch 79 unless the latch is urged out of its normal position. Thus for positive rotation of the bell crank 88 the end of balance lever 87 connected to link 81 is held downwardly. When the link 81 is allowed to rise by virtue of latch 79 being withdrawn, there is an associated rotation of bell crank 88 in a direction opposite to that produced by the selector latches being urged downwardly. If all of the latches 76, 77 and 78 are withdrawn from below the latch bail plate 67 and the five-unit latch is released to allow the link 81 to rise, a negative rotation of five units (the maximum negative rotation) occurs. If the selector latch 77, which as previously explained produces one unit of positive rotation is allowed to remain below the bail plate 67 and thus move downwardly therewith at the same time the link 81 is allowed to move upwardly, the total negative rotation is reduced by one unit and thus a four-unit negative rotation is achieved. Thus, through the combination of the five-unit latch 79 and the positive selector latches, a negative rotation of one, two, three, four, or five units can be achieved. The mechanisms employed for withdrawing selector latches and for driving the bail plate downwardly will now be described with reference to FIGS. 6 and 8.

The selection of a character or symbol to be printed is made through a key lever 101, one end of which is rotatably mounted on a fulcrum rod 102 and the other end of which is supported by a leaf spring 103. Depression of the key button 104 associated with the key lever 101 causes the key lever to move downwardly until it engages a lower stop 106. Mounted directly below each key lever 101 is an interposer 107, one end of which includes an elongated hole 108 through an interposer securing rod 109 passes. The elongated hole 108 allows the interposer to be moved a limited distance in the direction of its axis. The upper surface of the interposer includes a key-lever pawl contact surface 111 at the top of an upwardly projecting finger 112. The surface 111 engages the key-lever pawl 113 whenever the key lever is depressed and acts to transfer the downward motion of the key lever to the interposer 107. As the interposer moves downwardly, a downwardly extending clutch release lug 114 contacts a cycle bail 116 causing it to move downwardly.

As the cycle bail moves downwardly it engages the cycle clutch latch pawl 117 urging it downwardly so that it is able to slide under the cycle clutch keeper 118 which normally prevents the cycle clutch latch link 1 19 from moving toward the front of the typewriter (spring 103 being near the front while rod 102 is toward the rear) in which direction it is spring-urged by spring 105. With the pawl 117 disengaged from the keeper 118 the link can'move under the force of spring 105, and in so doing disengages the cycle clutch latch 121 from the cycle clutch sleeve 122 allowing the cycle clutch vto engage and thereby effectively connect the motor to the cycle shaft 14 for rotation thereof. Rotation of the cycle shaft 14 produces accompanying rotation of the filter shaft 19 which engages the end 123 of the interposer 107 when the interposer is in downward position. As the filter shaft rotates it drives the interposer toward the front of the typewriter within the limits set out by the elongated hole 108 and the rod 109. It is this movement which operates to select a character or symbol for printing. I

The filter shaft 19 also engages the cycle clutch latch restorer follower 124 which is connected to the cycle clutch latch restoring arm 120. The filter shaft causes clockwise rotation of arm which engages the cycle clutch latch bracket 121a and urges it in a direction which results in the cycle clutch 121 being put back to the condition in which it prevents the motor from being effectively connected to the cycle shaft.

Disposed directly below the interposer 107 are six selector bails 125-130. The selector bails are separated from one another by a distance which is slightly greater than the distance which the interposer is able to move within the limits set by the elongated hole 108. Extending downwardly from the underside of interposers 107 are zero to six selector lugs l3l which are affixed at any one of six possible locations along the underside of the interposer. Since there may be anywhere from zero to six selector lugs associated with an interposer, the number of selector bails associated with a given interposer may range from zero to six. There are 64 different unique combinations possible with the six bails and each interposer is associated with a different combination. In this way each key lever is associated with a different combination of selector bails through the selector lugs on an interposer 107.

When an interposer is driven toward the front of the typewriter by the filter shaft 19, it carries with it the selector bail or bails, if any, with which it is associated through its selector lug or lugs if any.

Each selector bail has exclusively associated therewith a latch interposer 132 (only two of which are shown in FIG. 6). Each latch interposer, in turn, is connected through a latch link 133 to one of the selector latches previously described with reference to FIG. 3. When a selector bail is moved towards the front of the typewriter it carries with it one of the latch interposers 132 which in turn operates through a link 133 to withdraw one of the selector latches from under the latch bail plate 67 of the latch bail 68 (see FIGS. 3 and 5). In this way each key lever is capable of selecting a different set of selector latches to be withdrawn from the latch bail and thus select a character or symbol for printing.

It is necessary for the operation of the present invention that the typewriter not only be remotely operable to print a character or symbol but also that it operate to generate an electrical signal which uniquely identifies the particular character or symbol selected for printing. Thus, if is necessary for the typewriter to be capable of both generating and operating in response to electrical signals. This last-mentioned feature can be provided (and has in fact been provided in prior art devices) by simply associating a solenoid with each of the key levers and through the use of a matrix or other logic device induce the desired operation by operation of the solenoid urging the key lever downwardly. Such a system is not satisfactory, however, because it is costly and cumbersome, due to the presence of a great number of solenoids. The present invention provides for both signal generating, and operation in response to electrical signals, in a unique manner which hasthe advantages of simplicity, accuracy, economy and of permitting unusually easy modification of the standard IBM selectric typewriter.

By detecting those of the six latches 61, 62, 76, 77, 78, 75, and 79, which are withdrawn in order to print a selected character or symbol, it is possible to state which of the 44 characters and symbols has been selected to be printed. This is true since each character occupies a unique position on the type head and each position on the type head is identifiable with a single combination of selector latches.

By associating eachof the six selector latches with an electrical signaling means which identifies those latches which have been withdrawn (or conversely those latches which have not been withdrawn) there will be generated, each time a character is printed, a six-channel electrical code signal representing'a six-bit binary word which is uniquely identifiable with a single character or symbol which the typewriter is capable of printing.

Referring to FIGS. 6 and 11, each of the six latch interposers 132 (one. of which is shown) is urged toward its associated selector latch by spring 134. A stop 136 limits the movement of the interposer in the direction of its selector latch such that when the end 137 of the latch interposer contacts the stop 136 the selector latch 61 (for example) is disposed such that its forwardly extending lower portion 61a is situated below the latch bail 67. When'these conditions prevail, the' selector latch is urged downwardly when the latch bail is driven downwardly. The particular latch interposer illustrated in FIG. 11 is associated with selector bail 126 through its upstanding latch interposer lug 138. When selector interposer 107 (FIG. 6) is driven toward the front of the typewriter by filter shaft 19, selector bail 126 is carried with the interposer by selector lug 131. The connectionbetween bail 126 and upstanding latch interposer lug 138 will result in the latch interposer 132 also moving toward the front of the typewriter. This operates to withdraw latch 61 from beneath the latch bail plate 67 and thus prevents the latch from being operated by the bail.

In order to provide one bit of the six bit word indicating the character selected, an interposer switch 601 is mounted to a switch mount plate 603 which, in turn, is mounted to the typewriter frame 605. The interposer switch 601 has a movable blade 607 which is seated in cam follower relationship against a portion of the interposer 132. The standard latch interposer currently used in the IBM selectric typewriter has a portion 604 which can be utilized as a cam lobe. A second blade 61 l of interposer switch 601 is positioned to be contacted by the movable blade 607. When the latch interposer 132is driven toward the front of the typewriter by the selector bail 126, the contact of removable blade 607 with the blade 611 provides an electrical signal indicating actuation of the latch interposer 132. A third blade 612 provides a signal indication that the interposer 132 has returned to its original'position.

Each of the six latch interposers are provided with similar interposer switches illustrated in FIG. 12. Each switch indicates the actuation of its associated latch interposer. For each character selected, a unique cornbination of latch interposers are driven forward by the filter shaft and actuate a unique combination of inter poser switches. The data from these interposer switches will provide a six bit word for each character selectable at the typing keyboard.

One of the most attractive features of the interposer switch is that it can be very easily added to the conventional typewriter by merely attaching the previously constructed switch to a switch mounting plate and mounting the plate to the typewriter frame 205. It is unnecessary to dismantle portions of the working mechanism of the typewriter. Furthermore, if servicing is needed, all interposers switches :are readily accessible for inspection, testing and servicing.

Each of the six latch interposers (shown collectively in FIG. 12 as 619) are also provided with a solenoid such as the solenoid 620 which is' connected to the latch interposer, such as the latch interposer 132 by means of a connecting rod'62l. This mechanism is illustrated in detail in FIG. 11 and is utilized when the typewriter is to function as a receiver of information from other remote sources. Each solenoid of the six, such as the solenoid 620, receives one bit fromthesix bit word indicating the character selected. This bit either causes the solenoid to be actuated or leaves the solenoid unactuated, depending on its magnitude.

The connecting rod 621 is provided with a clevis 623 which is connected to the latch interposer by. means of the clevis pin 625. The clevis pin 625 is already in position in a conventional selectric typewriter for holding.

the clevis 148 of the latch interposer 132. The opposite end of the connecting rod 621 is connected to the plunger 627 of the solenoid 620 by means of spring connector 629.

A mounting board 631 is mounted beneath the typewriter mechanism in a substantially horizontal orientation. The solenoid is attached to the underside of the mounting board. Similarly attached to the mounting board 631 is a bearing block 633 which is oriented transversely to the connecting rods such as the connecting rod 621. The bearing block 633 has a plurality of horizontal bores forming connecting rod bearings. The horizontal portion of each connecting rod, such as the connecting rod 621 is slidably mounted through one of the bearings.

Actuation of the solenoid 620 by an incoming bit causes the connecting rod 621 to act as a push rod and thereby push the latch interposer 132 towardthe front of the typewriter in the same manner that it would be pushed by the selector bail 126 if the typewriter keyboard were being utilized. Thus the six latch interposer solenoids cause the withdrawal of certain of the latches from the latch bail so that a character will be printed as described above.

The primary advantage of the present invention is the ease with which it can be attached to the conven tional-typewriter and its accessibility for purposes of servicing. It can be seen that the mounting board is merely mounted to the typewriter frame and that the clevis 623 on the end of the connecting rod 621 and the other five clevises need merely be: snapped on the al- 

1. In a remotely operable typewriter of the type having movable mechanical mechanisms for operating the character printers and the carriage functions, an actuating mechanism comprising: a. a mounting board horizontally mounted to the typewriter frame beneath the typewriter mechanisms; b. a plurality of horizontally operable solenoids mounted to the underside of the mounting board; c. a plurality of connecting rods connected to said mechanical mechanism and extending downwardly therefrom and thence horizontally beneath the mounting board and linked to the plungers of the solenoid; and d. a bearing block mounted to the underside of the mounting board having a plurality of horizontal bores forming connecting rod bearings and having a horizontal portion of each connecting rod slidably mounted through a different one of said bearings wherein the typewriter has a cycle clutch bail parallel to a keyboard lockout bail crank and wherein e. a tubular bearing sleeve is rotatably mounted to a portion of the lockout bail crank which is limited to rotational movement; f. a collar is secured to the lockout bail at each end of the sleeve in order to prevent axial sliding of the sleeve; g. bell crank arms are fixed to the sleeve to form a bell crank, one arm extending above the cycle clutch bail and the other arm extending downwardly to connection with one of said connecting rods. 